MM level 16 logic

[fawtytoo]

When you die or exit a level in MM, nothing is drawn in it's final positions. That is, it's all one frame behind the game logic. This is most noticeable in the "Sixteenth Cavern" when you drop into the portal, collect the final item and exit the level. If everything was drawn up-to-date, the final item would be erased and you would see Willy's feet below the portal. But that doesn't happen.

In order to address this and have the drawing up-to-date, I use an "Action" in my port that allows the game logic (ticker) and the drawer to complete before changing the state of the game. This works very well. Except for level 16. If I use the exact same level layout as the OG, as Willy falls through the portal to the final item, the item is collected. But as Willy is still falling, on the next frame he is no longer "inside" the portal and so falls onto the conveyor below. If I correct this, then I end up with the same visual anomaly as in the OG. Further fixes could be made but not without making the code unnecessarily complex for such a simple game.

My solution was the move the final item one tile lower. But that looks odd and begs the question as to why. To further the solution and add a "reason" for the change was the add a gap in the conveyor below the portal to make it more obvious as to why the item is lower. The "reason" given was to provide more of a challenge to get the final item.

On reflection, the final item should be placed immediately below the conveyor for the "challenge" and the conveyor gap was not necessary. But then why didn't Matt Smith do that?

The whole point of this is that I considered that final item to be pointless and didn't need to be there. I think this is analogous to the uncollectable item in JSW "Conservatory Roof" where the solution was to remove the offending nasty whereas another solution would be to remove/reposition the item.

@JianYang referred to my change as "very naughty". So I thought it needed a dedicated thread for the explanation/discussion.

[JianYang]

I was just trying to give others a little heads up while giving you a compliment in a "Yeah, you got me" kind of fashion while also trying to add a bit of humour. Clearly that didn't work out. Don't worry I like your version.

[fawtytoo]

I know you weren't scolding me (it's my port after all and I'll do what I want with it), but it made me think if I'd done too much to it on that level.

Level design, for any kind of game, usually avoids being designed that allows game engine bugs to creep in, which is what my post is about. That particular level illustrates that. I guess that the change I made was a kind of "that's how I would have done it" but now feel I've deviated from the OG which isn't the design goal. "Game play is 100% identical" I think is my claim. That level breaks that rule.

I'm just thinking out loud. Suggestion welcome.

[JianYang]

I'm glad we cleared that up.

Now your main question is pretty much a philosophical one. I don't have an answer, but I'll give you some thoughts.

In my head there are three classes of Manic Miner engines:

- Bug-compatible: I don't think they exist in the real world. Unless someone puts in the work to develop a Z80 recompiler, they might never happen.

- Bug-fixed: I think most engines are in this category.

- Loose recreations: Games that look like MM, but take lots of liberties.

I tried but couldn't manage to get stuck in a piece of wall, so I don't think you were going for bug-compatible.

For 15.8 levels it feels like a bug-fixed version and then when jumping into the exit I fall to my death. It is surprising. In a way it jumps from one category to another.

Do these categories matter to you? They may not even have existed outside of my head until I just wrote them down. Will this change surprise most players? Probably.

My gut reaction always seems to be: this should be more like the original. But then I can play the original pretty much on any device with a CPU and a display. In the end as a player I probably get more out of versions that take some liberties.

One more question might be: Did Matthew Smith intend people to collect the last item from below? We cannot be certain, but it looks a lot like it. Is it a design bug? Is it a design flaw? Maybe it's supposed to be troll?

Until I played the first version that changed this, I never even thought of my strategy to collect the last item from the top as a short cut.

Maybe as a final thought: the most extreme love letter to Manic Miner, @DigitalDuck's Manic Miner Redux, went the way of recreating the levels as original as possible and also including a second set of fixed/improved versions. Which might just show how difficult of a question this is.

That's a lot of thoughts without even really attempting to answer the question. Maybe this will help: There is no One True Way to do Manic Miner, trust your gut.

[fawtytoo]

15 hours ago, JianYang said:

One more question might be: Did Matthew Smith intend people to collect the last item from below? We cannot be certain, but it looks a lot like it. Is it a design bug? Is it a design flaw? Maybe it's supposed to be troll?

Did MS intend that item to be there? Is it a design bug/flaw? An oversight. Once the game is released it's too late. His contract would have mean meeting a deadline. You can only do so much testing. Supposed to be troll? MS understood game design principles but doesn't strike me as the sort that troll's.

[fawtytoo]

I just had a thought but I'm not sharing it. It will be an easter egg.

Edited January 17 by fawtytoo
To much sharing

[JianYang]

Maybe troll wasn't a great word, but in the cold room there's the shaft with the crumbling floors and next to it there's an empty shaft that looks like it would lead to fall damage/death. But if you have all the items collected you can exit the room through the empty shaft without getting hurt. So he sends you down a wrong path that takes a lot more time and is actually more dangerous than the drop through the empty shaft.

In this sense it could be a similar thing of showing the player a maneuverable path that he can choose to collect the item from below or take a much smaller risk and collect it from above. Red herring? False lead? I don't know what to call it, but there's a precedent for something like this.

But I agree most likely it's an oversight/design flaw.

Looking forward to your Easter egg.

[jetsetdanny]

There have been various interviews with Matthew Smith over the years. I wonder if he has ever been asked the questions that were asked in this thread. I can't recall any such interview, but that doesn't mean there wasn't one; I've always been more interested in new MM and JSW games than in details concerning the original ones.

Back in 2008, Andrew Broad created Manic Miner: Matthew Smith 2008 Remix, based on an interview with Matthew Smith in the Load 48 issue of Retro Gamer magazine. Here's an excerpt from its Readme regarding level 16 (or rather 15, since the first level is traditionally numbered as 0). This is just Andrew's interpretation, not Matt's "source knowledge". I highlighted the most relevant parts in bold.

 

[15] "Flag Bugs": '"I'd run out of names. Or maybe I was thinking in hexadecimal and thought it didn't need one," says Matt. And what are those enemies? "Flag bugs! In the code. If flag bug equals..."'
    I have put Water-cells in the portal to stop you simply dropping down to collect the item, although it does remove the need for a jump over the portal to collect the top-left item. I think it is more important to force the player to jump over the yellow flag-bug, which is obviously the route that Matthew Smith intended.
    I have added Fire 2 cells in the top row, just to show them. The Water 2 cells that I put in the portal actually look like switches, so it doesn't make much sense to make them visible.
    There is a hidden item in the room-definition, as the fifth item has a colour-attribute of 255, which terminates the sequence. So I have undeleted this item.

[fawtytoo]

Like I said before, MS clearly understood game design principles. In "Abandoned Uranium Workings" there are 2 seals that you don't go any where near, so why are they there? And yeah, which shaft do you use in the "Cold Room"? In "The Sixteenth Cavern", do you drop down through the exit to get that item and then get stuck because you didn't notice the item in the top left, or get the item in the top left and drop right down below the conveyor and go up to the last item?

Maybe MS knew the concept of speed runs. After all, the faster you complete a level, the higher your score.

Concerning MS interviews; there is one in his bedroom (I think) where he was asked where the boot came from in the Game Over screen in MM. MS answered with "the top of the screen". Obviously the interviewer meant where did the "idea" come from. Very funny answer.

Incidentally, I've reverted level 16 in my port to the OG layout. This discussion has helped me rethink that level. Thanks for your thoughts.

Edited January 18 by fawtytoo
bad wording